The present invention relates to a fluid product dispenser including:
a reservoir containing said fluid product and provided with at least one actuating wall on which pressure is exerted to reduce the reservoir volume,
a dispensing orifice communicating with the reservoir and through which the fluid product is dispensed out of the reservoir in a mixture with a gas to create a two-phase spray,
a detachable sealing unit to seal the dispensing orifice and so isolate the reservoir from the outside,
spring means to bring the actuating wall into a non-operational position defining the maximum reservoir volume when the sealing unit is withdrawn from the dispensing orifice, said spring means being compressed when the sealing unit seals the outlet orifice, the reservoir containing approximately only fluid product so long as the detachable sealing unit seals the dispensing orifice.
A fluid product dispenser of this type is particularly described in the document FR-2 791 645. The reservoir of this dispenser is therefore sealed by means of the detachable sealing unit when it contains practically only fluid product and practically no air or no air at all. It then has a particularly flat configuration, especially if a spring is used which adopts a flat configuration when compressed to the maximum. It is only when the detachable sealing unit is withdrawn that air is sucked into the reservoir through the dispensing orifice since the spring means are then able to relax and thus act upon the actuating wall so as to increase the reservoir volume to a maximum state. From this moment on, the reservoir contains a small quantity of fluid product and a much larger quantity of air. Now when the actuating wall is pressed, the reservoir volume diminishes and the mixture of air and fluid product is then forced back in the form of a two-phase spray through the dispensing orifice.
The advantage with a dispenser of this type is that the fluid product inside the reservoir is practically not in contact or not in contact at all with air which could cause deterioration in the qualities of the fluid product. However, the fluid product is in contact with the spring means which may be made of metal or of a plastic material. Depending on the type of fluid product contained in the reservoir, there may be a deterioration in its qualities given its direct contact with the spring means.
The purpose of the present invention is to overcome or at least to lessen the aforementioned drawback of the prior art by defining a fluid product dispenser with a sealed reservoir containing compressed spring means wherein the spring means are not in contact with the fluid product before withdrawal of the detachable sealing unit.
In order to meet this objective, the present invention proposes, so long as the sealing unit seals the dispensing orifice, that the reservoir is divided into several compartments by at least one partition, at least one of the compartments containing the fluid product and at least one other compartment containing the spring means, but no fluid product, in such a way that the fluid product is not in contact with the spring means before withdrawal of the sealing unit. To advantage, said at least one partition is adapted to break in such a way as to bring the compartments into communication with each other under the effect of the relaxation of the spring means after withdrawal of the sealing unit allowing air to penetrate into the reservoir through the dispensing orifice. There is therefore no particular or additional operation in respect of breaking the partition. Moreover, the means bringing about the rupture of the partition are mechanical, namely spring means. And mechanical means of this type have a force or more particularly a stiffness which is predetermined and easily measurable. Consequently, opening the partition to bring the different compartments together is not a random affair, as would be the case is the user were personally to effect the opening of the partition for example by pulling or pressing with one or more fingers. In the present invention, the user needs only to tear off or fold back the detachable sealing unit in order to open the dispensing orifice, which has the effect of triggering the relaxation of the spring means since air is able to penetrate into the reservoir. In this way, it is guaranteed that the partition will always be broken in the same way with given spring means. A particular advantage of the present invention lies therefore in the fact of using the relaxation of the spring triggered by the withdrawal of the detachable sealing unit in order to break the partition separating the spring from the fluid product and thus allow the fluid product and air to spread throughout the reservoir.
According to one characteristic of the invention, the spring means are located in a compartment able to be filled with air coming from the dispensing orifice after withdrawal of the sealing unit. Indeed, in order to allow the spring means to relax, it is necessary for them to be no longer isolated from the outside and for air to be able thereby to penetrate into the compartment where they are located.
According to one embodiment, the spring means are located in a compartment which communicates directly with the dispensing orifice. As a variant, the spring means are located in a compartment separated from the dispensing orifice by a selective partition impermeable to the fluid product and permeable to air. In this case, said selective partition may form a baffle which is impassable for the fluid product, but which nonetheless lets through air.
According to another characteristic of the invention, the compartment containing the spring means also contains a porous material component able to become saturated with fluid product by capillarity. As a variant, the compartment containing the fluid product also contains a porous material component able to become saturated with fluid product by capillarity.
This porous material component is preferably located in direct proximity to the dispensing orifice as is the case in the aforementioned prior art dispenser.
When the fluid product is located in the compartment also containing the porous material component, the compartment containing the spring means is separated from the fluid product compartment by the selective partition.
According to one practical embodiment, the dispenser includes two sheets of film welded together at their peripheries so as to form the reservoir, said at least one partition being formed by one or more low resistance weld lines able to come apart by separation of the sheets, to advantage caused by the relaxation of the spring means after withdrawal of the sealing unit. The weld at the peripheries of the sheets is a definitive weld whereas the weld forming the partition is a much weaker weld able to come apart without damaging the sheets.